incoherent
UK: ˌɪnkəʊˈhɪərənt | US: ˌɪnkoʊˈhɪrənt
adj. lacking logical or meaningful connection; disjointed
adj. unable to express thoughts clearly; unclear or rambling
adj. (physics) not coherent; lacking wave phase alignment
Derived from Latin incohaerens, combining in- (negation) + cohaerere (to stick together). The root haerere (to stick) evolved into her- in English, seen in words like "adhere" and "cohesion." Over time, "incoherent" shifted from literal "not sticking together" to figurative meanings of disorganized speech or logic. The physics sense (wave misalignment) emerged in the 19th century.
The fever made his speech incoherent and hard to follow.
The report was criticized for its incoherent arguments.
Quantum dots emit incoherent light under certain conditions.
After the accident, she gave an incoherent account of events.
His notes were a jumble of incoherent scribbles.